Add tests for legacy and per-thread default streams

[rongou]

Some simple tests to verify we are getting the correct default streams. Also added the capability to pass in additional compile flags for tests.

Part of NVIDIA/cccl#732.

@brycelelbach

[alliepiper]

The tests LGTM, but the CMake stuff is going to conflict with #1184.

We'll also need to update the Makefiles to make sure that this works with our current internal CI (which does not use CMake).

I'll take care of these issues once #1184 is merged and start testing integrating then.

Thanks for the patch!

[rongou]

@allisonvacanti merged with the new cmake files. Please take another look. Thanks!

[alliepiper]

@rongou Thanks for the updates and sorry about the long wait.

In general this looks ok, but I'll have to rethink this a bit from the CMake side since we need to support CUDA compilers besides nvcc. I'm planning to take a look at this sometime this week.

[alliepiper]

I'm fairly sure this will work on all of the NVIDIA compilers, just waiting on the nvc++ folks to confirm what their default behavior is.

[alliepiper]

Rebased on current main, restored original author metadata, and submitted DVS CL 28862904.